Don't EVER have a filter that is spilling back into the tank ABOVE the line of the tank...especially when the plants growing out of it might be able to redirect the water OUT of the tank, LOL. I had started with an aquaponics tank in a ten gallon. The water was pumped to the bottom of a glass vase filled with lava rocks and planted with various houseplants. The vase was lifted up out of the water on glass bricks and would spill over the edges back into the tank. Lovely looking tank, great working filter. Until a goldfish (I hate them & love them) one night decides to attack the roots of a diffenbachia I had growing in the gravel bed of the tank. He yanked it so hard (I know it was him because I've watched him try to do it before) the leaves of the diffenbachia got against the side of the vase, and slowly diverted the water out of my tank, into my dresser drawers, and onto my floor.
I had fallen asleep on the couch that night, and didn't notice until I woke up at 7 to get ready to teach a cooking class. I went to feed my fish and to my horror they were all flopping around in about 1/2 inch of water!
Amazingly everyone survived and is happily living in a 55 gallon tank filled half way. Same filter system since it works so well (but tank is tall enough to tower ABOVE the top of the filter), and just ordered a pocket grow tower to plant actual crops in this spring.
Don't! Leave things for later. Like securing plumbing. If it can get knocked loose and run your system water out onto the ground, it will eventually happen. Secure so it won't happen months later when you have forgotten that you never glued that connection. (glue is not required but make sure it is secured.) In tank plumbing that doesn't have to be water tight can be secured with a couple holes and a zip tie but don't leave it so the fish can knock it loose and get caught in the plumbing.
FYI ball valves are hard to operate when there is a fish in them!!!
that pic is just gross looking.. wtf
i had a big mistake a week ago, the system has been running over a year or more.
I had algae growing in an IBC FT so i thought i would kill it off by wrapping black plastic around it, it worked. I added some extra air to the water, but not enough, When the algae died it took alot of oxygen with it and my fish popped up dead overnight, i managed to save 15 cats and one bream, it probably killed 60 or 70 fish, most of them were new catfish fingerlings and bream.
It stunk pretty bad, had to fan out the 8x8 greenhouse so i wouldnt gag, Emptied the water to the tank, pressure washed it and filled it half way back with water.. I was thinking the whole time, i am so glad i did not put that tank in my band room / man cave. It would have been bad.
Another time i pulled the stand pipe around the bell siphon out, it collapsed with rocks and i killed alot of plants digging it out to fix it. I learned then to just leave things alone.
The other day I moved a can of fish food off a high shelf and placed it on the ground while retrieving other items off the shelf. I got side tracked and forgot to replace the fish food. My daughter found the can of food a little while later and decided to feed some fish. Instead of feeding normal the single cup of food, she fed then cup after cup and eventually the whole can ended up in the tank. I discovered this during the afternoon feeding but by then the food had been floating for so many hours that is was breaking down in the water. The bottom of the tank had a layer of food and the top had over an inch of floating food. When I finally got it cleaned there were a bunch of happy bloated fingerlings.
Don't leave fish food in the range of little hands!!
The other day I nailed down a peice of weed mat that kept popping up. I used some 1/4 lag bolts to secure the mat because it was the only thing I had around at the time.
A few days later I notices that I was not getting the air flow in the troughs that I was. After some searching I noticed a hissing coming from the ground under the weed mat.
Know and most importantly remember where your pipes are before driving anything into the ground!!
- Catching wild fish - ended up w a bad disease, it's just not worth it, buy fish from a good source and breed them if you can.
- adding pond plants - snails, snails, snails! I even hosed them off but there must have been some egg cases
- not watching the roots of perennial and long term plants like tomatoes in rafts. When you're not harvesting the rafts regularly you can end up w dead roots that look just like the photo Chris Smith posted above. The plants didn't die, but a good chunk of their roots did, I didn't notice, and ended up killing my favorite koi (a Gin Matsuba) and a couple other fish when they started to rot.
- not starting a system soon enough!!! I think you need to make a lot of errors to really learn about how aquaponics works. Reading and watching others will get you so far, but you learn so much more by doing it. Start small and leave room to grow because aquaponics quite addictive!